Fiber analysis - qualitative

Fiber analysis – qualitative on ‘fiber type’

DIN CEN ISO / TR 11827 describes many methods for determining the quality of fiber types. These include, microscopic procedures, chemical processes such as combustion. At CTL GmbH,  this list is supplemented by our own tests, which we have established through our experience.

Test description

Fibers can be roughly divided into two different types of fibers: natural fibers and synthetic fibers. Natural fibers include plant fibers such as cotton, linen, kapok, sisal and more exotic plants. Animal fibers are also natural fibers, as they are hair: wool, cashmere, angora, alpaca and many more. In addition, you can take silk, which is an animal fiber, but not a hair, but a secretion.

The synthetic fibers are the materials that are artificially produced and not harvested from nature. The materials can still be of natural origin, as is the case with viscose, for example. Here, cellulose from wood pulp is used to produce viscose. In other words, a synthetic fibers made from a natural raw material. Other well-known synthetic fibers, which are all made of plastic materials, are: polyester, poyamide, polyacrylic or polypropylene and several more.

In more recent times, special fibers also appear more frequently. These include bi-component fibers. Elastomultiester is one of them. These fibers consist of two different areas within a fiber. This leads to special properties. Elastomultiester, for example, acquires an elasticity that neither region would have on their own.

Not all fibers look the same. Cotton is twisted, linen resembles a bamboo structure, wool has scales on the surface, viscose has longitudinal stripes and most synthetic fibers are completely smooth. Especially the synthetic fibers can have other differences. Polyester can be produced, for example, as a round fiber, as a flat, oval fiber, as a hollow fiber or several other variants.

In the Textile Labelling Regulation 1007/2011, which stipulates the labelling of textiles in the EU, Annex I lists the types of fibers that may currently be present on a labelling. There are currently 50 types of fibers on this list.  We can identify all common fiber types. Only with exotics (very rare natural fibers or very novel synthetic fibers)  we are still in the learning process, as we have little experience for this. We rarely examine patterns of beaver hair. But we can distinguish cashmere from wool, both of which occur regularly.

If you buy a cashmere sweater for a lot of money, whether as an end user or as a retailer, then you also expect cashmere to be in it. When you buy a wool sweater, you don’t want to have polyacrylic with you. The legislator has clearly stated that all textiles in the EU must be labelled and that labelling must be accurate to within 3%. If your labelling is different, your product may be withdrawn from the market.

It sounds harsh and unnecessary that with a stated composition of 60% polyester and 40% cotton, your product is not marketable if you have used 55% polyester and 45% cotton. But that is the current legal situation. Considering that some fibers are cheaper, that this deceives the end user, then this strict interpretation makes a little more sense, even if it is still quite hard.

We can help you know what you’re selling. We know the labelling regulations and can tell you what to write on your label. The legislator is not completely open and there are various things that do not need to be labelled. For example, a 100% cotton sock does not necessarily have to be made of 100% cotton. We can clear these stumbling blocks for you, so that you do not have to familiarize yourself with them.

For the most part, we test microscopically for the fiber types. We use the methods described in DIN CEN ISO / TR 11827. At the same time, we use identifications that we have developed over the course of our financial years and which are less well known.


  • Fiber analysis – qualitative on bast fiber
  • Fiber analysis – qualitative on cotton
  • Fiber analysis – quality on cashmere
  • Fiber analysis – qualitative on wool
  • Fiber analysis – qualitatively based on regenerated cellulose fiber
  • Fiber analysis – qualitative on silk
  • Fiber analysis – qualitative on synthetic fiber
  • Fiber analysis – qualitative on elastane
  • Fiber analysis – qualitative on metal fiber
  • Fiber analysis – qualitative on merino wool
  • Fiber analysis – fiber thickness microscopically
  • Fiber Analysis – Inspection of the fiber Cross-Section

Required material for the test

  • About 2 g of each ingredient
  • If the composition of an entire article is to be determined, at least 1 entire article is necessary

Additional Tips

Even if something consists of 100% one type of fiber, it must always be thoroughly checked that there are no impurities or foreign fibers. Especially with recycled products, you often find unwanted foreign fibers, which can cause difficulties in the labeling if not tested.

How do we work

Our workflow



At the beginning, we clarify the scope of testing, the goal of the tests and, if applicable, the project requirements with the customer.



We prepare a quotation based on the scope of testing and the requirements



The order is clear and as soon as the test sample is received in the laboratory, we get straight to work with the sample.


Submitted test reports

The results are available in the form of a test report. In addition to the pure test result, an overall assessment according to legal, general or customer-specific requirements is possible.

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